docs: def url_to_string(url):
      """
      Return the contents of a web site url as a string.
      """
      try:
          page = urllib2.urlopen(url)
      except (urllib2.HTTPError, urllib2.URLError) as err:
          ui.error(c.MESSAGES["url_unreachable"], err)
          sys.exit(1)
  
      return page